Feeder keeps breaking filament

[Teslaismycopilot]

Hello everyone. It's my first post and of course it is a problem post.

So for whatever reason I will have a print fail and it will look like a clog or jam, the filament stops coming out the hotend. I will remove the bowden tube and try to feed the filament only to find it still doesn't move even when the hot end is involved. I look at the feeder system and the feeder (stepper?) has snapped the filament and isn't able to feed any new filament in. I pull out the broken filament thread and try again. My orion prints well for several hours and then this happens again. Are there any steps I can take to keep this from happening over and over again? I have a new Orion Delta, stock set up, SeeMeCNC PLA filament printing at 195-200 degrees. I have been having really perfect looking prints so far.

Thanks for your help.

[Nylocke]

You may be printing too low of temps, or your stepper may be running a tad hot. Generally this happens with really brittle filament or when there is excessive back pressure from the hotend (caused by too low of temps resulting in filament grinding). Is it actually snapped or does it look ground away?

The other possibility is that your stepper is heating up, softening the filament and pinching it off. This is least likely, so make sure it's not something else before you worry about the stepper heat.

[Teslaismycopilot]

So I may have been wrong about my issues. It's not about print time but more about WHAT I'm printing. At any stage where it has to extrude for a fine detail, retract, move, then extrude again that is where the filament stops moving forward and the gears just appear to turn. Here's an image of what I mean. The print moves fine until the printer is working on the top of the head and the top of the hands then it just gets worse until it is air printing. If I let it run for too long after this I can expect to find the filament snapped so maybe it is just grinding it in place or maybe it is retracting too much and just going over the same part of the filament with the gears? I'm not quite sure what to do any any help would be appreciated.

For what it's worth my stepper motor feels almost too hot to touch but the filament inside seems ground not melted.

[critical_limit]

Which Hotend you are using?
Which retract length and speed in the setting?

Nozzlesize?
Printingspeed?

[Teslaismycopilot]

All the hardware is the stock hardware that came with the device.

Manual rertaction speed is 30 mm/s
Print speed is at 100%
Diameter is 0.5 mm
retraction length is 7mm
lift z is 0.2 mm
speed is 80 mm/s
minimum travel after retraction is 3mm

I'm using the stock OrionPLA settings that I downloaded from the link in the manual with the exception of the temperature which I put up to 200

[critical_limit]

Hm, hard to say what´s wrong. I´m using only ABS for my prints, never used PLA.
But I would test following:

Retraction speed: 60 mm/s
Retraction length: 3 mm

printing speed: 50mm/s
nozzle temp: 210°C

layerfan and nozzlefan both 100%

[Teslaismycopilot]

Thanks for the suggestion. I'll give it a try and report back

[Nylocke]

What you're probably getting is filament grinding. That amount of retraction doesn't help either. The large amounts of quick retracts repeatedly over the same length of filament can grind it down.

[Teslaismycopilot]

I see, so is there any way to mitigate the grinding? Switching to another PLA or maybe some setting I could try?

[Mac The Knife]

lower your retraction length to 3mm for starters.

[Teslaismycopilot]

The retraction seems to have worked like a charm! I have more spiderwebbing but that is an acceptable outcome compared to full failure.

Thanks a lot for the help!

[critical_limit]

You didnt believe me, right?

try this like I said before:

Retraction speed: 60 mm/s
Retraction length: 3 mm

printing speed: 50mm/s
nozzle temp: 210°C

[critical_limit]

... and for the spider webbing reduce temps from try to try and/or increase retraction speed

[bot]

Also try increasing the minimum extrusion before retract. (In cura, I forget if slic3r has it). The default .01mm can allow a lot of retracts in a short time, even with minimum 3mm travel distance.

[RAMTechRob]

I have 500+ hours on mine and this same scenario happened to me. I switched to a new spool and put it in backwards, so the filament got caught at wierd times. Check that as well.

3mm for the retract works well for me. It looks like that solved your problem.